In an electronic device such as an AV receiver, there is a device which can update firmware via a network (for example, see JP 2015-138297 A.). An update package which is for updating the firmware is provided in a server. The update packages of one kind for each model are provided in the server. There are cases where CGIs for download are prepared in separate folders for a package for real update and a package for test and cases of update are divided.
However, a package which is updated is one folder for performance. For this reason, all electronic devices perform the same access. In this case, there is possibility that a problem that server accesses are concentrated and time is needed for download occurs because timing of accesses from the electronic devices to the server is the same. Further, there may be a problem that if there may be serious bugs in a released package, the package with the bugs is spread over as the package is updated all at once.